Shares of Mellanox Technologies, makers of chips that interconnect server computers, jumped by nearly 6% in late trading after it raised its quarterly revenue forecast only a month after offering it, citing growing demand for chips to upgrade connections of servers to 25 billion bits per second. The company also said its CFO will leave for a startup company.

Shares of Roku spent the entire after-hours session down 22%, but the company's chief financial officer, Steve Louden, tells Barron's he's heard no complaints from Wall Street analysts, and that "For us it's all been positive," with things like "platform revenue" and accounts using Roku rising sharply.

The ominous analysis illustrates potential dangers inherent in applying technology that literally takes on human characteristics, and what could go wrong. The Westworld-like doomsday scenario has prompted leading voices in technology to issue dire warnings.

Roku, the maker of appliances and services for viewing streaming video, saw its shares fall 21% in late trading after its quarterly results were ahead of Wall Street's expectations but it disappointed with its revenue forecast.